This invention relates to individual sections of multiple section glassware forming machines and to processes of forming glassware using such machine sections. A multiple section glassware forming machine comprises a plurality of sections arranged in side-by-side relationship, each such section in and of itself comprising a forming machine for converting a gob of molten glass at first into a parison and then into a finally shaped article of glassware. Each section may be designed for either "single gob" or "multiple gob" use--in the latter case each operation in the formation of multiple articles being performed at the same time. Accordingly, each such section includes at least one parison (or blank) mould in which parisons are formed either by pressing or blowing, and at least one final shaping blow mould wherein the parisons are blown into the final shape of the desired article of glassware as the result of the application of a pressure difference between the inside and the outside of the parison which is introduced into the blow mould.
In the conventional individual section glassware forming machine (the I.S. machine) such as shown for example in U.S. Pat. No. 1,911,119, the parison mould is in an inverted position at a first station and a transfer mechanism including a neck ring structure holds the inverted parison at the first station and swings the parison through an arc into an upright position in the blow mould at a second station for final shaping. The neck ring structure then reverts to the first station for subsequent parison formation. The final article of glassware is removed from the blow mould at the second station by a separate and independent takeout means.
The glassware forming process which is performed in the I.S. machine consists essentially of three stages, namely, a parison formation at the first station, a reheating time, and a final shaping of the article of glassware at the second station. The reheating time is the period within which the outer layer of glass which contacted the parison mould is reheated by the heat retained in the other parts of the parison and extends from the time at which the parison mould is opened at the first station until the time at which the final shaping of the article of glassware is commenced at the second station. In practice, for a given cycle time of the I.S. machine, the reheating time in the glassware forming process can be increased only at the expense of the time taken to blow the final article of glassware in the blow mould.
In U.K. Pat. No. 1,491,859 there is described an individual section of a multiple section glassware forming machine which comprises three stations being, respectively, a first station in which a parison is formed by pressing in an upright parison mould, a second station in which the parison is further formed, and a third station in which the final shaping of the article of glassware is effected in a blow mould. The glassware forming machine of U.K. Pat. No. 1,491,859 further comprises a transfer mechanism for parisons and finished articles of glassware which includes a horizontally movable carriage having thereon a neck ring structure and two tong structures. The carriage is reciprocated linearly from one position to another position and back to the said one position between successive parison formations at the first station, with the result that there is simultaneous movement of a parison from the first station to the second station, a further formed parison from the second station to the third station, and an article of glassware from the third station to a take-out position beyond the third station, for example a deadplate. In the process of forming glassware using this machine, adequate reheating time is provided in consequence of the sojourn of the parison at the second station, but there is again little scope for variation of the reheating time which is frequently rather longer than is required at the expense of time which is desired for suspending the finished article after removal from the blow mould at the third station and before being deposited, for example, on a deadplate. This desirable article hanging time (also referred to herein as "deadplate hanging time") can only be provided in the machine of U.K. Pat. No. 1,491,859 at the expense of the time taken to press the parison at the first station.